Leverless inking mechanism for rotary printing machines



April 25, 1961 P. DIETRICH 2,981,182

LEvERLEss INKING MEGHANISM FOR ROTARY PRINTING MACHINES Filed April l0, 1957 2 Sheets-Sheet 1 R -M/M@ April 25, 1961 P. DIETRICH 2,981,182

LEvERLEss INKING NEcHANIsM FOR ROTARY PRINTING MACHINES Filed April l0, 1957 2 Sheets-Sheet 2 LEVERLESS INKING MECHANISM FOR ROTARY PRINTlNG MACHINES Paul Dietrich, Augsburg, Germany, assignor to Maschinenfabrik Augsburg-Numberg A.G.,} Augsburg, Germany This invention relates to a leverless inking mechanism for rotary printing machines, wherein the ink is supplied to a cylinder of an inking mechanism by means of a pump. This is a continuation-in-part application of my copending application Serial No. 538,230, now abandoned, iledk October 3, 1955 for A Leverless Inking Mechanism for Rotary Printing Machines.

Hitherto, pumps have, on the one hand, been used for feeding the ink uniformly and homogeneously, but the volume of ink fed cannotbe regulated. On-the other hand, variable delivery piston pumps are also known. However, these do not enable the ink to be fed in a uniform and homogeneous manner, but merely feed intermittently, and only a single piston stroke occurs during several revolutions of the cylinder of the printing or inking mechanism.

However, the ink pump mechanisms so far known possess the disadvantage that the delivery of ink thereby is not satisfactory so that good quality printing does not result.

The present invention aims at removing the disadvantages mentioned above. According to the present in- `vention there is provided a leverless inking mechanism for rotary printing machines of the kind in which the ink is delivered to a cylinder by means of pumps, wherein the pumps each comprise a rotor driven by a shaft and having outwardly sliding vanes, means being provided whereby the volume of ink delivered thereby may be varied, the arrangement being such that the ink is delivered in a homogeneous condition. A multiplicity of pump elements, arranged within a common ink reservoir, are expendiently provided in order to ensure uniform delivery and regmlation of the ink over the width of the cylinder. Several variable capacity vane pumps are advantageously arranged with the centers of their rotors on a common driving shaft, and several shafts are advantageously disposed in side-by-side relationship in the ink reservoir. In order that ink delivery may be regulated in accordance with the speed of the machine, the driving shafts are coupled together in a suitable manner, for example by gear-wheels, and coupled to a driving element, the speed of which is dependent on the speed at which the machine is driven. In addition, the quantity of ink can be individually and variably regulated by the adjustable construction of the housings of the pump element. The driving shafts provided with the rotor elements of the pumps are constructed in known manner as lubricant guides for the slots in which the vanes slide. The ink contained in the ink reservoir is itself used as a lubricant, and is fed to the hollow driving shafts and the slots in which the vanes slide by means of a gearwheel pump arranged in the ink reservoir and coupled to the element which drives the pump shafts. The inking mechanism according to the invention has the advantage that the delivery of ink can be regulated, is completely uniform, homogeneous and dependent on the speed of the machine.

The use of variable capacity vane pumps ensures a linear output of ink at all pump speeds. Thus the quantity of ink varies in the same ratio as the speed of the printing press, and the pumps are driven from a driving element dependent on the speed at which the press is driven. Furthermore, the individual adjustability Yof each pump enables exact control at all pump speeds and the accurate matching of the quantity of ink required with respect to the printing surface in use. In this connection, in carrying out the invention, it is of secondary importance whether the ink is delivered to the cylinder by means of nozzles or spraying devices.

For a better understanding of the invention and to show how the same may be,l carried into effect, reference will now be made to the accompanying drawings, in which:

Figure 1 is a plan View of an inking mechanism according to the invention in diagrammatic form;

Figure 2 is a section along the line II-II in Figure 1 to a` larger scale;

Figure 3 is a section taken along the line Ill-III in Figure l; and

Figure 4 is a cross-sectional view through a modified form of vane pump.

In the drawings, 1 designates an ink reservoir containing the pumps 2, each of which is of the outwardly sliding vane type. A multiplicity of such pumps are located within the ink reservoir so that the ink can be uniformly distributed over the whole width of the cylinder, and several pumps are mounted on a common driving shaft 3 supported within the pump housing. Several driving shafts may also be arranged in side-by-side relationship, as can be seen from Figure 1. The driving shafts carry gear-wheels 4 at one end, and are driven through suitable pinions by a worm wheel 5 and a Worm 6 from a driing element which is dependent onV the speed at which the machine is driven. As can be seen from Figure 2, each pump substantially comprises a housing 7 and a rotor 8, having a series of radially arranged slots in which the outwardly sliding vanes 9- are carried. The pump housings 7 are capable of being adjusted independently for each pump by means of screws 10 rigidly supported by the cover of the ink reservoir, so that the quantity of ink fed by the individual pumps can be regulated and matched with respect to the printing surface in use. The quantity of ink fed can be correspondingly varied by upward or downward adjustment of the screws 10. The pumps themselves are arranged in the ink reservoir, and aspirate the ink in the direction indicated by arrows through bores 11 in the partitions 12 of the reservoir, and feed the ink through the pipe 13 to delivery nozzles or a spraying device. The method of delivering the ink to the cylinders does not form part of the invention, and consequently is not described in detail. According to the invention, the ink itself is employed for lubricating the sliding vanes of the pumps. For this purpose, the driving shafts 3 are of hollow construction and communicate -via bores 15 with the slots in which the vanes 9 slide, as shown at 14. The ink serving as a lubricant is fed by a gear-wheel pump 16 via a pipe 17 (see Figure 3) to the hollow shaft of the individual rows of pumps, and proceeds thence through the bores 15 to the slots in which the vanes 9 slide respectively through the bores 212 to the upper and lower bearings 23 and 24 of the driving shaft 3. The bearings are fastened together and to the bottom of the ink reser- In the modification of Figure 4, a self-lubricating vane pump of increased ink capacity is used in place of the pump 2 and oil bores of Figures 1 to 3. Each housing '7a has a cylindrical opening therein Withinwhich is eccentrically mounted the rotor 8a which has slots containing the vanes 9a. Springs 30 have one end seated on the bottom of the slots, with the other end teleseoped into hollow space 32 in the vanes. At low pump speeds as from about 0.05 to 2.50r.p.rn., the centrifugal force on vanes 9a is not great enough to hold the'outer ends' of the vanes against' the pump housing. Consequently, springs 30 keep the varies so engaged at the low pump speeds, and thus hold the tolerance of the amount of ink deiivered at all pump speeds. f

Each vane has a groove 34 whichV forms a passage- Way atording communication between the periphery of rotor 8a and the space 36 beneath the base of the vane 9a. Ink therefor can flow from the input space 3S of the pump to the space 36, and also into hollow space 32. Consequently, the volume of ink moved is increased by use of the spaces 32 and 36.

This pump makes it possible to assure a steady supply of ink to the cylinders, while at the same time producing a morevoluminous ow of ink.

An additional feature resides in the fact that the outer edges 40 are beveled.

Having now described the means by which the objects of the invention are obtained, I claim:

1. In the combination of an ink pumping mechanism for a rotary printing press having an ink reservoir, a plurality of kparaliel rows of ink pumps mounted in said reservoir and separated by paraliel partitions, the irnprovement comprising each ink pump being a variable capacity vane pump having an independently adiustable housing with a cylindrical opening therein, a rotor ecceutrically mounted in said housing, a common drive shaft extending through the centers of all the rotors in a row of pumps, a Wall common to each pair of adjacent pumps and extending between parallel partitions for forming a bearing for said shaft and a side for each independentiy adjustable housing, slots in said rotor, vanes slidably mounted in said slots, grooves in said vanes forming passages for liquids from the periphery of said rotor to the spaces beneath the bases of said vanes, and springs seated on the bottoms of said slots andfbearing on saidyane's to urgevthe latter outwardly of said rotor and into engagement with the Wall of said cylindrical opening.

2. In the combination of claim 1, said` vanes being hollow with said springs telescopicaliy mounted therein.

3. in the combination of claim 2, said vanes having beveled outer edges.

4. in the combination of claim 3, further comprising feeding and drainage bores in said partitions.

5. 1n the combination of claim 1, said bearing means each comprising a two piece bearing supporting a single piece drive shaft andvane rotor.

References Cited in the le of this patent p UNITED STATES PATENTS McElroy et al. Aug. 22, 

